Drilling device provided with a multi-bladed drilling tool, especially a deep drilling tool

ABSTRACT

The invention relates to a multi-bladed deep drilling tool ( 17 ) comprising a cooling lubricant channel ( 19, 20 ) provided for each chip space ( 74 ) allocated to each cutter ( 71 ). Said channels ( 19,20 ) are supplied with a lubricant independently from each other, by means of either jointly drives or separately drives lubricating pumps ( 25, 26 ). Said channels being associated with either the drilling devise ( 11 ) or integrated into an adapter ( 30 ) which is pivoted with a common flow of lubricant, but which supplies independent individual flows. Lubrication of the individual cutting zones is guaranteed even if the chip removal channel is blocked, by chips for example. The pressure of the cooling lubricant channel increases in said area whereupon the channel in question is cleared.

FIELD OF APPLICATION AND PRIOR ART

The invention relates to a drilling device with a multiblade drillingtool, particularly a deep drilling tool, having at least two supplychannels by means of which cooling lubricant is supplied to the cuttingzone.

In addition to the frequently used single-flute deep drilling tools, useis also made of multiblade deep drilling tools, together with otherdrilling tools such as e.g. twist drills. In the case of heavy dutydrills, particularly deep drilling tools, the cutting zone is suppliedwith cooling lubricant along penetrating channels via the drill and thisserves to cool said cutting zone, lubricate guide sections of the drilllocated in the hole and in particular remove the chips arising duringdrilling. For this purpose chip removal channels are provided in thedrill, e.g. in the form of an axially directed recess (mainly in thecase of deep drilling tools) or helical channels in the case ofso-called twist drills.

Whereas in the case of single-flute drills having only a single blade,the chip space or chamber formed upstream of the blade andcorrespondingly also the removal channels are relatively large, withmultiblade drills the cross-section thereof is limited. With long-chipmaterials, e.g. in the case of steel as opposed to aluminium or castmaterial, the long, helical chips formed easily lead to blocking orclogging of the chip removal channels.

PROBLEM AND SOLUTION

The problem of the present invention is to ensure the supply of thecutting zone in the case of drilling devices of the aforementioned type,i.e. multiblade drilling tools, even with clogging-prone materials.

According to the invention this problem is solved in that with thechannels are associated independent cooling lubricant supply devices.These are preferably constructed for maintaining predetermined, separatevolume flows of the cooling lubricant for the individual channels.

It is assumed that with each blade is associated a supply channel forthe cooling lubricant normally issuing into the drill end face followingon to the leading blade and supplies the chip space of the followingblade behind the same in the rotation direction. This produces the chipswhich are removed in the chip space and the following chip removalchannels through the hole. If clogging occurs in one of the chip spacesand the associated removal channels as a result of long chips and inparticular chip balls which form, as a result of the independent supplywith lubricant of the associated supply channel it is ensured that saidblade and its chip space, together with the following chip removalchannel are still supplied with lubricant. If all the supply channelswere connected to the same cooling lubricant supply device, e.g. acommon pump or pressure line, then if clogging occurred the coolinglubricant pressure would only insignificantly rise and a correspondinglylarger quantity would flow therefrom to the supply channel belonging tothe unclogged channel system. This would not put an end to clogging orblocking and the associated blade would not receive an adequate coolinglubricant quantity. This can bring about seizing up and damage ordestruction of the complete drill and workpiece. The bore or hole wallcan be damaged by the clogging in the outwardly open removal channels.

According to the invention, in advantageous manner the supply devicesare constructed for increasing the cooling lubricant pressure in thecase of a reduction of the volume flow in one of the channels as aresult of clogging. Thus, the pressure rises in accordance with thesupply device design to such an extent that the blockage is removed.

This can be brought about in that to the channels are in each caseconnected independent pumps or independent pump chambers in the case ofpumps having several chambers. However, it is also possible to connectthe channels to outlets of a quantity divider. Such a quantity dividere.g. operates in the manner of a gear pump with several chambers, whichare driven by the supplied medium and at their individual outlets ineach case deliver predetermined, e.g. identical volume flows. These aresubstantially independent of the pressures prevailing in the individualoutlet lines, apart from the clearance losses in the quantity dividermechanism, etc. As a result it is possible to implement the inventioneven in the case of a drilling device with only a central supply for thecooling lubricant. The quantity divider, like the separate supply linesto the channels, can be provided in an adapter, which is connected to adrilling spindle and e.g. contains the chuck for the drill. However, itis also possible to bring about the above-described behaviour of thecooling lubricant pressure and volume flow in the individual channels bya corresponding volume/pressure control or to modify, e.g. increase thesame compared with the natural pressure rise on reducing the volumeflow. It is also possible in this case to produce specific pressureimpulses or surges, which contribute to a release of blockages. Thiscould take place by the provision of pressure and/or quantity sensors inthe independent supply line systems by means of an electronic orhydraulic control device acting on pumps and/or valves.

The introduction of the cooling lubricant into the individual channelsin an independent manner can take place in different ways. Theprerequisite is that there are separate supply channels in the tool.These can have axial, radial or axial and radial inlets in the arearemote from the drill point, which are generally supplied by means ofrotary ducts with circulating ring grooves. These can once again beintegrated into or connected to the previously described adapter ordrilling spindle.

The invention also proposes a drilling device in which the chip spacesformed in front of the blades in the working rotation direction of amultiblade drilling tool and which are connected to the chip removalchannels, have a rounded side wall connected to the blade.Conventionally the chip spaces in the cutting heads of drilling toolsare circular segmental in cross-section. This also applies for twistdrills, where admittedly as a result of the helical shape of the chipspace or the removal channels a rounding is present, but which stillhave a substantially circular segmental cross-section. The angularcorner which forms close to the drill centre and also the corners formedbetween the bore wall and the chip space boundary form attachment pointswhere chips can become attached and adhere so as to form starting pointsfor blockages.

As a result of the rounded side wall not only is a relatively large chipspace created, particularly if it extends up to the centre plane of thedrill perpendicular to the blade, but said sharp corners are avoided. Inaddition, chip guidance surfaces are created along which the chips slidedown and “screw” outwards e.g. in a helical manner through the removalchannels, which preferably have the same shape with rounded side walls.

Moreover, due to the fact that in this construction a projectionprojecting circumferentially into the chip space is created, despite alarge chip space a surface is formed acting as a guidance zone for thedrill and which is e.g. somewhat increased in diameter compared with thestandard drill circumference and consequently serves as a work guide.Particularly with an asymmetrical blade arrangement, it absorbs reactionpressures and ensures a precise guidance of the drill in the alreadyformed hole, which renders possible axial precise drilling, particularlywith deep drills.

A further inventive measure for preventing blockages and removalproblems with respect to long chips formed, is brought about in that amultiblade drilling tool, considered in an axial plan view on the drillend, has a bend on one of the blades where the two blade sections meetunder an angle, which is preferably between 170ø and 120ø. This can e.g.arise in that at some distance from the drill centre the blade bends inthe rotation direction or passes with a radius into a new orientation.Thus, the chip space is further enlarged. The bent blade ensures thatthe chips break more easily and do not arise as a relatively wide,coiled strip which can stick in the removal channels. Instead twotightly juxtaposed, narrower chip strips are formed, which should reallystill adhere in the centre, but as a result of the different formationconditions the chip can tear longitudinally and also transversely, whichleads to a chip pattern corresponding to a short-chip material. Thismeasure can in the case of a two-blade drill e.g. be provided on bothblades, so that the drill once again has a symmetrical cutting pattern,but is advantageously only provided on one blade. In this case, as aresult of the different cutting geometry, deliberately a transverseforce is produced on the drill head, which for a clear engagementpresses one of the guide zones onto the hole wall and consequentlyprevents all guidance problems as a result of the mutual engagement ofthe drill. Thus, a deliberate asymmetry of the blades is created.

The present invention is particularly advantageous for deep drilling,but also provides advantages for other drilling work, e.g. cooling ducttwist drills and countersinks. It is also appropriate with a double andmultiple supply of cooling lubricant to one blade.

These and further features can be gathered from the claims, descriptionand drawings and the individual features, both singly or in the form ofsubcombinations, can be implemented in an embodiment of the inventionand in other fields and can represent advantageous, independentlyprotectable constructions for which protection is claimed here. Thesubdivision of the application into individual sections and thesubheadings in no way restrict the general validity of the statementsmade thereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention are described hereinafter relative to theattached drawings, wherein show:

FIGS. 1 to 4 Diagrammatic side views of a drilling device with differentpaths for the cooling lubricant supply.

FIG. 5 A diagrammatic longitudinal section through a deep drilling tool.

FIG. 6 A cross-section along line VI-VI in FIG. 5.

FIGS. 7 & 8 Details of other embodiments of a drill according to FIG. 5with different cooling lubricant supplies.

FIG. 9 An adapter with a rotary duct for the lubricant.

FIG. 10 An adapter with a quantity divider for cooling lubricant.

FIG. 11 A front view of the working side of a deep drilling tool.

FIG. 12 A section through the associated pipe section forming the drillshank.

FIGS. 13, 14 & 15 Views corresponding to FIG. 11 of differently designeddrills.

FIG. 16 A view of the drill in the direction of arrow XVI.

PREFERRED EMBODIMENTS

FIG. 1 shows a drilling device 11 with a machine frame 12 on which aheadstock 14 is horizontally displaceable on a carriage 13 and is guidedin infeed manner corresponding to the drilling advance. A drillingspindle 15 is mounted in rotary and drivable manner in the headstock 14.On one side of the drilling spindle a drilling tool 17, e.g. a deepdrilling tool is clamped in a chuck 16. In the manner describedhereinafter, said tool has two cooling lubricant supply channels 19, 20running longitudinally up to its cutting zone 18 at the free end andwhich issue into the drilling tool end face 21 forming said cuttingzone.

At the end of the drilling spindle 15 opposite to the drilling tool isprovided a rotary duct 22 receiving cooling lubricant for the hole orbore by means of two separate supply lines 23, 24. The latter aresupplied by two separate pumps 25, 26 or two pump chambers of the samepump, which can be driven by a common motor 27. They draw the coolinglubricant 28 out of a storage tank 29. In a manner to be describedhereinafter relative to FIG. 9, in the rotary ducts the coolinglubricant coming from the machine-fixed supply lines 23, 24 areintroduced into axial channels in the rotary drilling spindle and fromthere into the drilling tool in such a way that each of the channels 19,20 receives cooling lubricant, except for the transfer leakage losses,from in each case one of the supply lines 23, 24.

FIG. 1 shows that the supply lines 23, 24 issue radially into the rotaryduct 22, where the line path is transformed into an axial guide withinthe drilling spindle from where it is passed into axial channels in thedrilling tool.

FIG. 2 shows a construction of a drilling device 11 corresponding inprinciple to FIG. 1, where the supply lines 23, 24 are connected to anadapter 30, as shown in FIG. 9. There is no rotary duct transferring thecooling lubricant from the connected to rotate supply lines, but whichare axially displaceable with the headstock 14 to an inner partrotatable with the drilling spindle and drilling tool, from whereintroduction takes place into the channels 19, 20 of the drilling tool17.

FIG. 3 shows a construction in which the supply to the channel 19 takesplace by means of a rotary duct 22 a at the chuck 16 or an adapter part,introduction taking place radially.

Channel 20 is supplied by means of a rotary duct 22 b which, much as inFIG. 1, is located at the spindle end, where introduction of thelubricant takes place by means of an axial infeed 24. This constructioncan be advantageous if the drilling device already has a coolinglubricant guide for a single channel and for application of theinvention a second, independent supply line is added.

FIG. 4 diagrammatically shows a construction in which, much as in FIG.1, the supply lines are connected to a rotary duct located at thedrilling spindle end, but with a supply line 23 with an axial and asupply line 24 with a radial issuing into the same.

FIG. 5 shows a section through a deep drilling tool 17. It contains acutting head, which is mainly made from hard material and is fitted,e.g. by soldering, to an elongated shank 32 which can be referred to asa pipe. The latter is in one piece or connected to a clamping head 33,which can be clamped in a clamping chuck on the drilling spindle. In theexamples shown, the cutting head, shank and clamping head 33 contain twochannels 19, 20, which pass as through, particularly mutually aligned,axially parallel bores through the entire tool and have their openings34 in the cutting head end face 22. In the cutting head and shank areformed two chip removal channels 35, 36 (cf. FIG. 6), which areconstructed as segment-like cutouts in the otherwise circularcylindrical cross-section of shank and cutting head. FIGS. 1 and 6 showa full or solid material shank construction. In the constructionaccording to FIG. 5, the channels associated with the supply channelsare guided independently of one another through the drilling spindle(coolant infeed according to FIG. 1 or 4).

In the embodiment according to FIG. 5 the connection of the channels 19,20 in the drilling tool 17 is axial, i.e. the corresponding channels inthe drilling spindle or clamping head end in an axial end face and therering seals surrounding the channels are provided. This could be adrilling device according to FIG. 1 or 4. Instead of frontal inlets 37,38 according to FIG. 5, the construction according to FIG. 7 has afrontal inlet 38 and a radial inlet 37, formed by a connecting bore tothe blind hole-like channel 19. This construction would be suitable fora drilling device according to FIG. 3.

FIG. 8 shows an example in which two radial inlets 37, 38 are axiallyspaced from one another and are supplied by means of corresponding ringchannels in the adapter or clamping head.

FIG. 9 shows an adapter containing a rotary duct 22. The adapter has abody 39, which is to be connected by means of a flange 40 and screwssymbolized by their centre lines to the rotary drilling spindle. Therotary duct 22 is placed on the cylindrical section 41 in the form of aring 42 surrounding said section 41 and which is provided on its innerface 43 with two axially spaced annular grooves 44, 45, which areconnected to the cooling lubricant connections 23, 24 by means of radialbores. Ring 42 can rotate on the cylindrical section 41 of body 39, butis so arranged or so sealed by not shown sealing rings that there is nosignificant connection between the cooling lubricant flows from thesupply lines 23 and 24.

At both ends of the ring 42 are provided further annular grooves 46,which are used for removing any leaking oil and for this purpose areconnected to corresponding leaking oil drains 47.

In the body 39 is provided a central, inner bore, which extends from thedrilling tool-side end 48 over and beyond the annular groove 45 andwhich serves to receive the clamping head 33 of drilling tool 17. Thelatter is fixed by means of a clamp nut 49 with associated screw cap 50to the adapter and consequently form the chuck 16. In the interior ofthe bore 51 is located the clamping head 33 passing over three doublering webs 52 in each case forming between them a groove in which islocated an O-ring 53, thereby bounding two ring chambers 54, 55 sealedagainst one another. In the vicinity of these sections bounded by thering chambers issue the tool inlets 37, whose inlet design is similar tothat of FIG. 8.

In the tubular wall of body 39 are provided, parallel to the systemcentre axis 56, holes 57, 58, from which cross-holes 59, 60 extend tothe annular grooves 44, 45. Thus, independently of one another, they areconnected to the supply lines 23, 24 and via further cross-holes 61, 63to the ring chambers 54, 55. From there the cooling lubricant can flowinto the channels 19, 20 in the drill via inlets 37 in section 55 and 38in section 54 (cf. FIG. 8). The longitudinal and transverse channels arein part constructed as drilled-through channels with terminating pieces.Thus, it is clear that the adapter can be placed on the spindle, e.g. ofa deep drilling machine and on the one hand has the chuck and on theother the rotary duct for an independent double guidance of the coolinglubricant.

Whereas FIG. 9 with respect to the cooling lubricant volume and pressurerequires independently supplied or controlled supply lines 23, 24, theadapter 30 a of FIG. 10 can be connected to a drilling device, whichonly has a common cooling lubricant supply line 63. In the embodimentshown it is supplied through the drilling spindle to which the adapteris connected by means of the flange 40 on its body 39.

A quantity divider 64 is integrated into the adapter 30 a and isdirectly installed in the body 39 and constructed in the manner of adouble gear pump. It correspondingly comprises two double gear pairs 65,66, whose gears are arranged in spaced manner in each case on one shaft67 and are mounted in rotary manner in the body 39 or a pump-closingcover 68, which also carries the supply line 33. In each case one sideof the meshing gear pairs is connected to the supply line 63, whilst theother side is connected to two independent chambers 69, 70, which areconnected by means of a system of longitudinal and cross-holes to thelongitudinal holes 57, 58, whose construction and function cancorrespond to those of FIG. 9. The connection of the drilling tool 17 inthe remaining part of the adapter can also correspond to that of FIG. 9.

Thus, the quantity divider also has the common pressurized coolinglubricant supply line 63, which passes into the driving chambers of thequantity divider 64, i.e. the two inlet-side chambers of the double gearpump 65, 66. As a result the quantity divider is driven, i.e. the twogear pairs rotate in opposition and sealed, meshing manner with theshafts 67 and deliver the cooling lubricant on the outlet side, i.e.into chambers 69, 70. Due to the mechanical coupling of the two gearpairs through the shafts 67, the same cooling lubricant quantity is fedinto both chambers 69, 70, once again apart from leaks. Despite a commonsupply line, the two outlets are pressure-decoupled in the longitudinalholes 57, 58, but are quantitatively coupled together. By means of thesame quantity divider structure it is possible to separate from oneanother random partial quantities and, should this prove necessary, canplace the volume thereof in a specific ratio, which need not always be1:1.

Other quantity divider constructions are also possible, e.g. based onthe plunger cell pump principle. As such quantity dividers can beconstructed in uncomplicated, very compact manner, they are particularlysuitable for use in an adapter. However, a quantity divider can also beprovided outside the spindle arrangement or drilling device. Theadvantage of the arrangement described is that only one rotary duct isrequired for a single cooling lubricant strand.

FIG. 11 is a plan view of the end face 21 of a deep drilling tool 17 or,more precisely, the hard material cutting head 31 (cf. also FIG. 5).There are two blades 71 extending symmetrically to either side of thedrilling tool centre 72. The end face 21 is generally somewhat conicalunder a blade angle conventionally used for deep drilling tools andwhich is usually between 20 and 45ø, measured with respect to a plane onwhich the drill axis 56 stands perpendicularly. This is the angleassumed by the blades. In special cases the blade angle can also be 0ø,e.g. for producing a flat hole bottom in a blind hole. The remainingpart of the end face is set back somewhat for creating a clearanceangle. In the outer area the blades 71 are bounded by an axiallydirected edge, whereas in the central area where the drill “presses” dueto lower circumferential speeds, they have a roof-shape.

Upstream of the blades 71 in the working rotation direction 73 is ineach case formed a chip chamber or space 74, which is bounded by one ofthe two blades 71, a side wall 75 and a worked hole or bore wall 76indicated in broken line form. The side wall, which extends from theblade up to the bore wall 76, is rounded and extends up to a verticaltransverse plane 77 through the drill centre 72. Thus, the chip space 74formed has a size of almost a quarter of the cross-section, the anglesor corners of said sector being generously rounded. In FIG. 11 the sidewall is virtually a semicircle around a centre point positioned roughlycentrally in the chip space. Thus, in the vicinity of the centre, isformed an admittedly narrow, but very strong central web 78 as a resultof the generous rounding and is traversed in inclined manner by the twoblades. The rounded side wall forms an arcuate, triangular projection79, which could also be referred to as a gusset, which extends thecircumferential line left behind of the cutting head in the direction ofthe chip space. In this area and somewhat beyond the central plane 77 isformed a guide zone 80, namely through a circumferential linesubstantially precisely corresponding to the desired bore or holediameter and which is limited to the vicinity of the guide zone and theblade ends, whereas the cutting head circumference in the remaining areais set back by a small amount compared therewith ( 1/100 to 1/10 mm).

In the vicinity of the end face 21 “left behind” in the area between thechip spaces 74 are provided the openings 34 of channels 19, 20, whichallow the discharge of cooling lubricant just behind the in each caseleading blade and which subsequently enters the chip space 74 andcarries the chips produced there by the blade 71 through the followingremoval channels 35, 36.

FIG. 12, which is a cross-section through shank 32, shows the removalchannels. It can be seen that the removal channels, like the supplychannels, have in the shank area the same shape and arrangement as inthe vicinity of the cutting head.

The advantage of the rounded shape of the chip space 74 and removalchannels 35, 36 is that the chip helixes particularly forming with verytough and therefore long-chip materials cannot become attached as aresult of the rounding and instead in the virtually circular chip andremoval area pass in the form of a helix to the outlet in the vicinityof the clamping head.

FIG. 13 shows a view corresponding to FIG. 11 for which all the featuresof the latter apply, with the exception of the shape of the rounded sidewall 75. Instead of being virtually a semicircle as in FIG. 11, it ishere constructed as a half flat oval. Close to the centre of the blade71 is connected a radius 81 which is smaller than that in FIG. 11. Thus,web 78 is even narrower. Following a short, straight intermediate piece82 is then connected a somewhat larger radius 83, which also forms aprojection 79, but which is somewhat smaller than in FIG. 11. Here againthe chip space 74 is well rounded and sufficiently large to remove inblockage-free manner the chips produced by the blade.

FIG. 14 shows a construction which, in the lower right-hand part issimilar to that of FIG. 13, whereas in the upper, left-hand part has amodified structure with respect to the blade shape.

At some distance from the centre 72, the blade 71 a has a bend 84(considering the front side, i.e. according to FIG. 14). Based on theworking rotation direction 73 of said tool (clockwise), the upper bladepart 85 is tilted rearwards, so that the extension of the blade nowpasses somewhat above the centre instead of close to the latter. As thewall of the chip space 74 axially adjacent to the blade is adapted tothe blade shape, i.e. is also “cut away” there, the chip space openseven further towards this side. The auxiliary blade can preferablyassume one to two quarters of the total length of the blade 71 a(cutting head radius), particularly approximately half.

As a result of this construction two advantages are obtained. Firstly,as a result of the bent shape of the blade the chip is longitudinallybroken, i.e. two narrower chips are formed which, also due to thetransverse forces resulting from the bend, tear or break more easily.Secondly as a result of the fact that one blade is straight and theother bent, a certain transverse force is produced which, as a functionof the conditions, presses one of the two guide surfaces 80 onto thebore wall 76, without neutral intermediate phases arising in which thetool could become “unsteady”. Otherwise the side wall 75 is constructedin the upper, left-hand area in accordance with FIG. 11.

FIGS. 15 and 16 show a construction in which the two blades 71 a areconstructed with a bend 84, top left in FIG. 14. Thus, here on bothsides a very large, open chip space 74 is formed and on both sides thechips are kept narrow and short in the above-described manner.

FIG. 16 shows that despite the bend the side view of the cutting head 31is substantially roof-shaped, the basic shape of the end surface 21consequently being conical. Express reference is made to the drawingsconcerning the precise design and dimensions, particularly of theblades, chip spaces and removal channels.

Function

On the basis of FIG. 1, the drilling device fixed in a drilling spindle15 is applied to a workpiece and the said spindle is rotated by a notshown motor. Motor 27 is started up, so that it forces cooling lubricantvia supply lines 23, 24 into the drilling device and consequentlythrough the axial channels 19, 20 and to the cutting head openings 34.The drill, which is normally guided at its workpiece-near end in a drillbush, is then moved up to the workpiece, up to which the headstock 14 onthe carriage guide 13 is moved by an infeed drive. The two blades workinto the workpiece and cut the same. The chips are carried by thecooling lubricant through the chip spaces 74 and the removal channels35, 36 in shank 72 and are discharged just before the end of the drill,i.e. upstream of the clamping head. For this purpose the drilling devicehas a not shown chip container, where the cooling lubricant is collectedagain and optionally in reconditioned form returned to the tank 29.

Normally the counterpressure in both supply channels 19, 20 is the same,so that even without the separate supply via the two pumps 25, 26 thepressure and volume in both channels would be identical. However, ifclogging or some other obstacle occurs, particularly in the chip spaceor removal channels, the pressure in said zone rises. Due to theindependent, substantially volume-constant cooling lubricant supply toeach individual channel, in the clogged channel, instead of a reductionin the flow quantity, the pressure is significantly increased until theblockage is flushed clear.

In the construction according to FIG. 10 with a quantity divider, theboring device has only one pump and one supply line 63. The twoindependent, substantially identical volume flows with optionally adifferent pressure level are produced by the quantity divider in themanner described relative to FIG. 10.

FIGS. 11 to 16 show that through the rounded side wall 75 or 81, 82, 83of chip spaces 74 and the in any case preferably identically constructedremoval channels 35, 36 in shank 32, the clogging risk is relatively lowand this is further aided by the bent blade 71 a. As a result, the cutchips are longitudinally broken apart substantially in the centre. Thedrilling tools permit a heavy duty operation, even in the case ofotherwise difficult to drill, long-chip material.

1. A drilling device comprising: a multiblade drilling tool having acutting zone with at least two blades, the drilling tool having: atleast two internal supply channels by means of which cooling lubricantis supplied to the cutting zone, the supply channels passing through thefull length of the drilling tool; and at least two external removalchannels in addition to the supply channels, wherein the coolinglubricant and chips are removed from the cutting zone by means of theremoval channels, the removal channels being formed by cutouts on theoutside of the drilling tool, wherein each of the at least two internalsupply channels is individually associated with only one of at least twoindependent cooling lubricant devices.
 2. The drilling device accordingto claim 1, wherein the supply devices are constructed for maintainingpredetermined, separate volume flows of the cooling lubricant for theindividual channels.
 3. The drilling device according to claim 1,wherein the supply devices are constructed for increasing the coolinglubricant pressure in the case of a reduction of the volume flow in oneof the channels as a result of a blockage.
 4. The drilling deviceaccording to claim 1, wherein independent pumps or pump chambers areconnected to the channels.
 5. A drilling device comprising a multibladedrilling tool having: at least two supply channels by means of whichcooling lubricant is supplied to the cutting zone; and removal channels,wherein cooling lubricant and chips are removed from the cutting zone bymeans of the removal channels, wherein the supply channels areassociated with independent cooling lubricant supply devices, and areconnected to the outlets of a quantity divider.
 6. The drilling deviceaccording to claim 1, wherein the cooling lubricant supply is located ina drilling spindle or an adapter.
 7. The drilling device according toclaim 1, further comprising a rotary duct for the cooling lubricant. 8.The drilling device according to claim 1, wherein the introduction ofthe cooling lubricant into the drilling tool or drilling spindle takesplace radially, axially, or radially and axially.
 9. The drilling deviceaccording to claim 1, wherein chip spaces having a rounded side wall incross-section are located adjacent and upstream of the blades in aworking rotation direction of the multiblade drilling tool, the chipspaces being connected to the removal channels.
 10. The drilling deviceaccording to claim 9, wherein the chip removal channels also have arounded side wall.
 11. The drilling device according to claim 9, whereinthe rounded side wall extends approximately up to a drilling tool centreplane perpendicular to the blade.
 12. The drilling device according toclaim 11, wherein, in the vicinity of the drilling tool externaldiameter, the rounded side wall bounds a substantially circumferentiallydirected projection projecting into the chip space.
 13. The drillingdevice according to claim 9, wherein the rounded side wall has thecross-sectional shape of a semicircle or half a long oval.
 14. Thedrilling device according to claim 1, wherein at least one of the bladesof the multiblade drilling tool, considered in an axial plan view on thedrilling tool end face, has two blade sections that meet at an angle toform a bend.
 15. The drilling device according to claim 9, wherein thedrilling tool has a cutting head and a shank applied thereto, the shankhaving recesses forming chip removal channels, wherein thecross-sectional shape of the chip removal channels is the same as thecross-sectional shape of the chip spaces.
 16. A drilling devicecomprising: a multiblade drilling tool having a cutting zone with atleast two blades, the drilling tool having: at least two internal supplychannels by means of which cooling lubricant is supplied to the cuttingzone, the supply channels passing through the drilling tool; and atleast two external removal channels in addition to the supply channels,wherein the cooling lubricant and chips are removed from the cuttingzone by means of the removal channels, the removal channels being formedby cutouts on the outside of the drilling tool, wherein the supplychannels are associated with independent cooling lubricant devices, thedrilling device further comprising an adapter with independent coolinglubricant infeeds in two separate supply channels in the drilling tool.17. A drilling device comprising multiblade drilling tool having: atleast two supply channels by means of which cooling lubricant issupplied to the cutting zone; removal channels, wherein coolinglubricant and chips are removed from the cutting zone by means of theremoval channels; and an adapter with independent cooling lubricantinfeeds in two separate supply channels in the drilling tool, whereinthe supply channels are associated with independent cooling lubricantsupply devices, and wherein a quantity divider is provided in theadapter.
 18. The drilling device according to claim 16, wherein theadapter contains a chuck for the drilling tool.
 19. The drilling deviceaccording to claim 1, wherein a drilling spindle is mounted in aheadstock and there is a separate cooling lubricant infeed for the twochannels into the drilling spindle.
 20. The drilling device according toclaim 1, wherein the multiblade drilling tool is a deep drilling tool.21. The drilling device according to claim 1, wherein the drilling toolhas exactly two blades and exactly two supply channels, wherein eachblade is associated with a supply channel.
 22. The drilling deviceaccording to claim 6, wherein the drilling spindle or adapter contains aquantity divider.
 23. The drilling device according to claim 22, whereinthe drilling spindle or adapter contains the chuck for the drillingtool.
 24. The drilling device according to claim 19, wherein the coolinglubricant infeed is located at the end of the drilling spindle remotefrom the drilling tool.
 25. The drilling device according to claim 14,wherein the bend has an angle between 170° and 120°.